Delaware & Hudson 4-6-2 "Pacific" Locomotives in the USA

Class P (Locobase 3076)

[] published locomotive diagrams that showed the superheat at 840 sq ft, an increase over the original size.

Firebox heating surface includes 40 sq ft (3.7 sq m) of arch tubes.

Because these engines used the big anthracite-burning grate, one can draw a misleading conclusion about this design's ability to steam, particularly in reviewing the A/S ratio of tube/flue cross-section to grate area. Coincidentally, the Railway Age article (14 December 1914) describing these engines makes the point a different way: "According to the method of boiler proportioning used [by Alco], these ...engines have 111 percent boilers." RA explains that 100 percent means ample steam-making capacity, but passenger engines should have some in reserve.

Given the D&H's limited passenger demands these engines were quite worthy and ran until 1952-1953.

Class P-1 (Locobase 143)

Data from 1933 D & H Description of Locomotives books supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.Chicago, St Paul, Minneapolis & Omaha. (Many thanks to Chris Hohl for his 22 September 2017 email reporting unlikely boiler pressure values for 177 entries. A Locobase macro caused the error .)

Although laid out according to orthodox American design, these three engines had a British look in their clean boilers, thick and wide face shield below the smokebox, and plain smokebox face with headlight centered. Two had poppet valves and one piston valves -- all were experimental and did not lead to large classes.